6 files changed, 8 insertions, 1 deletions

diff --git a/include/linux/tcp.h b/include/linux/tcp.h
index 8a7fc4be2d75..60b7aac15e0e 100644
--- a/include/linux/tcp.h
+++ b/include/linux/tcp.h
@@ -191,7 +191,8 @@ struct tcp_sock {
         u8      do_early_retrans:1,/* Enable RFC5827 early-retransmit  */
                 early_retrans_delayed:1, /* Delayed ER timer installed */
                 syn_data:1,     /* SYN includes data */
-                syn_fastopen:1; /* SYN includes Fast Open option */
+                syn_fastopen:1, /* SYN includes Fast Open option */
+                syn_data_acked:1;/* data in SYN is acked by SYN-ACK */
 
 /* RTT measurement */
         u32     srtt;           /* smoothed round trip time << 3        */
diff --git a/include/uapi/linux/tcp.h b/include/uapi/linux/tcp.h
index c4b89a5cb7df..e962faa5ab0d 100644
--- a/include/uapi/linux/tcp.h
+++ b/include/uapi/linux/tcp.h
@@ -130,6 +130,7 @@ enum {
 #define TCPI_OPT_WSCALE         4
 #define TCPI_OPT_ECN            8 /* ECN was negociated at TCP session init */
 #define TCPI_OPT_ECN_SEEN       16 /* we received at least one packet with ECT */
+#define TCPI_OPT_SYN_DATA       32 /* SYN-ACK acked data in SYN sent or rcvd */
 
 enum tcp_ca_state {
         TCP_CA_Open = 0,
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c
index b7c2f439b54f..197c0008503c 100644
--- a/net/ipv4/tcp.c
+++ b/net/ipv4/tcp.c
@@ -2764,6 +2764,8 @@ void tcp_get_info(const struct sock *sk, struct tcp_info *info)
                 info->tcpi_options |= TCPI_OPT_ECN;
         if (tp->ecn_flags & TCP_ECN_SEEN)
                 info->tcpi_options |= TCPI_OPT_ECN_SEEN;
+        if (tp->syn_data_acked)
+                info->tcpi_options |= TCPI_OPT_SYN_DATA;
 
         info->tcpi_rto = jiffies_to_usecs(icsk->icsk_rto);
         info->tcpi_ato = jiffies_to_usecs(icsk->icsk_ack.ato);
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index 432c36649db3..036f85738141 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -5646,6 +5646,7 @@ static bool tcp_rcv_fastopen_synack(struct sock *sk, struct sk_buff *synack,
                 tcp_rearm_rto(sk);
                 return true;
         }
+        tp->syn_data_acked = tp->syn_data;
         return false;
 }
 
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index ef998b008a57..0c4a64355603 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1461,6 +1461,7 @@ static int tcp_v4_conn_req_fastopen(struct sock *sk,
                 skb_set_owner_r(skb, child);
                 __skb_queue_tail(&child->sk_receive_queue, skb);
                 tp->rcv_nxt = TCP_SKB_CB(skb)->end_seq;
+                tp->syn_data_acked = 1;
         }
         sk->sk_data_ready(sk, 0);
         bh_unlock_sock(child);
diff --git a/net/ipv4/tcp_minisocks.c b/net/ipv4/tcp_minisocks.c
index 27536ba16c9d..a7302d974f32 100644
--- a/net/ipv4/tcp_minisocks.c
+++ b/net/ipv4/tcp_minisocks.c
@@ -510,6 +510,7 @@ struct sock *tcp_create_openreq_child(struct sock *sk, struct request_sock *req,
                 newtp->rx_opt.mss_clamp = req->mss;
                 TCP_ECN_openreq_child(newtp, req);
                 newtp->fastopen_rsk = NULL;
+                newtp->syn_data_acked = 0;
 
                 TCP_INC_STATS_BH(sock_net(sk), TCP_MIB_PASSIVEOPENS);
         }